Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
  • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B7/00—Insulated conductors or cables characterised by their form
  • H01B7/17—Protection against damage caused by external factors, e.g. sheaths or armouring
  • H01B7/29—Protection against damage caused by extremes of temperature or by flame
  • H01B7/295—Protection against damage caused by extremes of temperature or by flame using material resistant to flame
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
  • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
  • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
  • H01B3/42—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes polyesters; polyethers; polyacetals
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
  • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
  • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
  • H01B3/42—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes polyesters; polyethers; polyacetals
  • H01B3/421—Polyesters
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2927—Rod, strand, filament or fiber including structurally defined particulate matter
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2933—Coated or with bond, impregnation or core
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2933—Coated or with bond, impregnation or core
  • Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2913—Rod, strand, filament or fiber
  • Y10T428/2933—Coated or with bond, impregnation or core
  • Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
  • Y10T428/2958—Metal or metal compound in coating

Definitions

• This invention relates to covered electric wires for transmission of energy or information, in which the cover comprises a halogen-containing flame retardant aromatic polyester copolymer which has thin coating capabilities, and more particularly, which contributes toward space saving through line thickness reduction, and which has excellent heat resistance, flame retardancy, and mechanical properties particularly flex resistance.
• electric wires whether used for line transmission or within artefacts have two roles, namely, energy transmission and information transmission. They are required to involve low energy loss in the process of transmission and also to exhibit reliable performance through accurate response to information signals.
• covered electric wires are required to meet these conditions: that the covered wires should be as thin as possible in order to realise space saving; that they should have sufficient flexibility to cope with odd-shaped space and folding at sharp angles; that they should have high heat resistance and high flame retardancy; and that they should have good resistance to contact wear due to vibration in order to prevent short circuiting due to covering-­material wear. In addition, they are required to have good electrical properties.
• strands have been used as conductors, while natural rubber, synthetic rubber, polyvinyl chloride, polyethylene, polypropylene, nylon, and the like have been used for covering materials.
• polyvinyl chloride has been largely used from the standpoint of flame retardancy and of mechanical strength.
• Nylon and the like in which the resin itself has heat resistance, has excellent mechanical properties, but it lacks moisture resistance; as such, these resins are liable in considerable deterioration in their physical properties and are not reliable when they are applied as thin coatings.
• Other engineering plastics such as polyphenylene sulfide and polyether imide, can satisfy the heat resistance requirements, but they have some deficiency in respect of flexibility. As such, these plastics involve considerable difficulty in property balancing and further they are economically disadvantageous.
• crystalline polyesters such as polyethylene terephthalate and polybutylene terephthalate
• polyethylene terephthalate and polybutylene terephthalate have hitherto been used because of their favourable properties including mechanical strength, heat resistance, and electrical characteristics.
• a composition comprising a blend of polyethylene terephthalate or polybutylene terephthalate with polyolefin, or to blend a special grafted polyolefin resin with polyethylene terephthalate.
• polyester resin compositions have also been found unsatisfactory for electric wire covering with regard to the balancing of flame retardancy and coat thickness reduction relative to protective characteristics and wear resistance.
• the present invention provides a covered electric wire for use in the transmission of energy or information whether by line or cable transmission or within artefacts, characterised in that the covering material comprises a halogen-containing flame retardant aromatic polyester copolymer produced by condensation polymerization of
• wire in the form of strands Whilst the form of electric wire used in the present invention is not limited, from the standpoint of flexibility and of reliability it is preferred to use wire in the form of strands.
• a preferred type of strand is that which has been passed through a compression stage in the process of manufacture so that its conductor surface is smoothed so as to facilitate thin coating and such that gaps between strands are narrowed for space saving.
• compressed strands are preferred. More particularly, circular compressed strands are preferred for the convenience of precise controlling of thin coating at the stage of wire covering.
• the material of the conductor may be aluminium, copper, tin-plate copper, aluminium alloy, or the like. These materials may be selected according to the purpose for which the conductor is used.
• the thickness of a covering insulator for the conductor of an automotive transmission line is subject to limitations by the processability and covering characteristics of the covering material used, but it is desirable that the covering insulator be as thin as practicable. Hitherto, the thickness of the covering material could not be reduced below the limit of 0.9mm - 0.6mm from the view points of both electrical and mechanical characteristics and, more particularly, from the view point of wear resistance of a thin coat. According to the present invention, however, it is possible to provide a coat thickness of 0.4 mm, or even less than 0.3 mm.
• a covering insulator for an automotive transmission line should desirably have the following properties: (a) flame retardancy such that flame will die out within 30 seconds, preferably within 15 seconds, after ignition; (b) ease of bending and good flexibility, that is, high extensibility of the order of more than 100%, preferably 125%, at ordinary temperatures, and (c) high wear resistance such that the minimum wear resistance is of the order of more than 305 mm according to JIS C 3406, in view of the fact that where the transmission line is used at a location adjacent a source of vibration, it is necessary to prevent short circuiting due to friction between covering materials, as well as their friction with adjacent components.
• the flame retardant substance is incorporated in the copolymer molecules, whereby a much better balancing of properties can be effected as compared with the admixture of separate compound.
• the incorporation of a halogen compound in a copolymer eliminates the possibility of flame retarder leaching, and as a secondary advantage, enables wire-to-­wire blocking to be effectively avoided in the process of manufacture which will be hereinafter described.
• polyester copolymer used in the present invention will now be described in detail.
• constituent (A) consists principally of an aromatic dicarboxylic acid or its ester-forming derivative.
• a typical example of such substance is terephthalic acid or its derivatives.
• dicarboxylic acids such as isophthalic acid, naphthalene carboxylic acid, and naphthalene dicarboxylic acid, or their derivatives
• aliphatic acids such as adipic acid, sebacic acid, trimellitic acid, and succinic acid, or their ester-forming derivatives
• aromatic hydroxycarboxylic acids such as hydroxybenzoic acid and hydroxynaphthoic acid, or their ester forming derivatives.
• Constituent B of the polyester copolymer of the invention consists principally of an aliphatic diol or its ester forming derivative.
• a typical example of such substance is low molecular weight glycols of C2 - C8.
• ethylene glycol, 1,4-butylene glycol, 1,3-propane diol, 1,4-butene diol, 1,6-hexane diol, and 1,8-octane diol are mentioned as such.
• a high molecular weight glycol such as poly­alkylene oxide glycol, may also be used.
• polyethylene oxide glycol, polybutylene oxide glycol, or the like may be used as such.
• aromatic alcohols such as bisphenol A and 4,4 ⁇ -hydroxybiphenyl
• alkylene oxide adduct alcohols such as an ethylene oxide 2 mol adduct of bisphenol A, and a propylene oxide 2 mol adduct of bisphenol A
• polyhydroxy compounds such as glycerine and pentaerythritol, or their ester-­forming derivatives.
• the polyester copolymer as a covering material for the covered electric wires of the present invention is an aromatic polyester copolymer in which an ester-­forming compound containing a halogen is used in the form of a monomer as constituent (C), whereby the halogen is combined into the molecular structure of the copolymer.
• halogen-containing compounds useful for this purpose are illustrated below.
• bromine is particularly preferred
• Halogen compounds preferred for incorporation as a copolymer compound are those expressed by general formulas (1) - (7).
• the halogen is bromine
• examples of compounds coming under general formula (a) are tetrabromo bisphenol A and tetrabromo bisphenol sylfone
• an example of compounds under general formula (2) is tetrabromo bisphenol F
• examples Of those under general formula (3) are an ethylene oxide 2 mol adduct of tetrabromo bisphenol A, a propylene oxide 2 mol adduct of tetrabromo bisphenol A, an ethylene oxide 2 mol adduct of tetrabromo bisphenol sulfone, and a propylene oxide 2 mol adduct of tetrabromo bisphenol sulfone;
• an example under general formula (4) is tetrabromo hydroquinone
• an example under general formula (5) is an ethylene oxide 2 mol adduct
• the molecular weight of the halogen compound for incorporation in the copolymer composition is preferably more than 390. If the molecular weight is smaller, the compound will not contribute toward improvement in the oxygen index. Preferably, the compound should have at least one of more aromatic ring in its molecule.
• the halogen compound may be added so that the proportion of the halogen compound in the copoly­ester produced is 0.5 - 20 mol % preferably 1 - 15 mol%,.relative to the entire monomer units (A + B + C) which constitute the copolyester. This corresponds to a halogen content of 1 - 30 wt%, preferably 2 - 25%, in the copolyester. If the proportion is less than 0.5 mol%, no satisfactory flame retardancy can be obtained. If it is more than 20 mol%, some degradation in mechanical properties will result.
• Proportions of monomers for preparation of the polyester copolymer in the present invention should be such that where the ester-­forming functional group of the halogen compound as consituent (C) is alcoholic, the proportion of constituents (B) + (C) be 90 - 200 mol, preferably 95 - 100 mol, relative to 100 mol of constituent (A). If the ester-forming functional group of the halogen compound as constituent (C) is of the carboxylic acid system, the proportion of constituent (B) should be 90 - 200 mol, preferably 95 - 150 mol, relative to 100 mol of constituents (A) + (C).
• the copolymer to be used in the invention may be prepared by known condensation-polymerization techniques, such as interfacial polycondensation and melt bulk polymerization. Any such copolymer having an inherent viscosity of 0.5 - 3.0 is useful for the purpose of the invention.
• the resin composition used as the covering material has a relatively high viscosity when molten.
• excessively high viscosity is detrimental to the mechanical properties of the material.
• the covering material of the invention exhibits excellent performance characteristics without the presence of any particular additive therein.
• stabilizers as anti­oxidant and ultraviolet light absorber, antistatic agents, flame retardants, flame retarding asisstants, such colorants as dyes and pigments, and other substances for fluidity and releas­ability improvent, such as lubricants, lubricating agents, crystallization accelerators (nucleating agents), and inorganic materials.
• antimony compouns such as antimony trioxide and antimony halide
• metallic compounds such as zinc and bismuth
• clay-type silicates such as magnesium hydroxide and asbestos
• inorganic fibers such as glass fiber, ceramic fiber, boron fiber, potassium titanate fiber, and asbestos
• powder and granular materials such as calcium carbonate, highly dispersible silicate, alumina, aluminum hydroxide, talc, clay, mica, glass flakes, glass powder, glass beads, quartz powder, silica sand, wollastonite, carbon black, barium sulfate, plaster of paris, silicon carbode, alumina, boron nitride, and silicon nitride; and lamellar inorganic compounds, whiskers, and the like.
• Such inorganic fillers may be used for admixture in one kind or in a combination of two or more kinds.
• polymeric materials are other kinds of polyesters, polyamides, polyolefins, and their copolymers, low molecular-weight polyethylenes, polycarbonates, polyurethanes, rubber-like polymeric materials, such as butyl rubber are ABS, multi-phase copolymers composed of polyacrylates, thermoplastic segment-­type copolyesters (including graft copolymers), and phosphoric compounds.
• the covered electric wire of the present invention may be manufactured by known techniques. Usually, the covering material is coated on a running line of conductor as it is melt extruded. There are two ways of manufacturing, one in which the direction of conductor run and the direction of extrusion of the covering material are collinear, and the other in which a cross head having a certain angular position is employed.
• the transmission line of the invention can be manufactured in either way.
• Detection of thickness irregularities of the covering material is carried out by employing known techniques, such as X-ray and ultrasonic methods.
• concentricity e c any eccentricity of the covering material due to its thickness irregularity is expressed in terms of concentricity e c .
• e min minimum thickness of coat section
• e max maximum thickness of coat section
• Thickness irregularity control is performed by detecting such irregularity by means of a eccentricity detector, then adjusting the clearance between the die and the conductor at the die center of the screw-type extruder either auto­matically or manually, or by controlling the flow rate of the covering material in conjunction with pressure and temperature control.
• the wire In the process of manufacture, if so required, it is possible to pass the wire through a heating zone after the covering material is coated thereon and shaped, in order to further improve the mechanical strength of the covering material.
• the temperature of the heating zone should be lower than the melting point of the covering material and higher than the glass transition point thereof.
• the covering material used in the invention has the flame retarding compound incorporated in the copolymer, and therefore, it is free from the possibility of flame retarder or plasticizer leaching at high temperatures as is often seen with polyvinyl chloride compositions; therefore no wire-to-wire blocking is likely to occur in the process of manufacture. This permits higher speed wire coating and contributes toward a saving in production cost.
• the wire covering material of the invention provides the following advantages.
• the covered electric wire of the present invention can be advantageously employed particularly as a low-voltage transmission line, and is applicable in various other ways in such areas as transport equipment, electric and electronic appliances, information equipment, and various machines.
• Copolymers P, Q, and R were prepared in the following ways respectively.
• the reactor was gradually subjected to pressure reduction so that the pressure in the reactor was reduced to 0.5 mmHg in 15 minutes. Agitation was carried out under this pressure at 270°C for 4 hours.
• the polymer thus obtained had an inherent viscosity of 1.1 and a Br content of 6.5 wt%.
• a reactor having an agitator, a nitrogen introduction pipe, and a distillation pipe were charges 931 parts of dimethyl terephthalate, 39 parts by weight of dimethylene isophthalate, 513 parts by weight of 1,4-butane diol, and 171 parts by weight of a propylene oxide 2 mol adduct of tetrabromo bisphenol sulfone, together with a small amount of a catalyst (0.7 part by weight of tetrabutoxy titanium), and the nixture was sturred under a stream of nitrogen gas at 170°C for 30 minutes. The temperature was gradually raised and the mixture was heated at temperatures of 200°C to 270°C under stirring for 3 hours.
• the reactor was gradually subjected to pressure reduction so that the pressure in the reactor was reduced to 0.5 mmHg in 15 minutes. Agitation was carried out under this pressure at 270°C for 3.5 hours.
• the polymer thus obtained had an inherent viscosity of 1.0 and a Br content of 6.3 wt%.
• the reactor was gradually subjected to pressure reduction so that the pressure in the reactor was reduced to 0.5 mmHg in 15 minutes. Agitation was carried out under this pressure at 270°C for 6 hours.
• the polymer thus obtained had an inherent viscosity of 1.0 and a Br content of 6.5% by weight.
• Test specimens were prepared from copolymer produced in Prepartion 1, by employing an injection molding machine in conventional manner. Tensile strength (kg/cm2) and elongation (%) measurements were made according to ASTM D 638. Dielectric breakdown measurements were made according to ASTM D 149 short-term method, and dielectric constant measurements were made according to ASTM D 150, at 1 kHz. Flammability tests were made according to UL-94V; in these tests, where flame died and within 30 seconds, specimen was rated o, and where flame did not die out within that time, specimen was rated x. Oxygen index measurements were made according to JIS K7201. For surface configuration of molded part when heated, tests were made by heating the molded part in air at 120°C for 24 hours. Presence of leaching (x) or no leaching (o) on the moulded part was visually examined. Test results are shown in Table 1.
• copolymer P was coated on a copper round compressed strand of about 1.9 mm outer dia, at thickness setting of 0.3 mm and 0.4 mm.
• An adjustment region for discharge pressure of a gear pump was provided between the die and the screw, whereby discharge pressure was automatically controlled.
• Mean concentricity values for the covering material for the covered electric wires were 72% and 77% respectively.
• wear resistance measurements were made at 20°C and 60° according to JIS-C 3406 and by employing a 1350g weight. Where minimum wear resistance value was more than 305 mm, the sample was rated o, and where such value was less than 305 mm, the sample was rated x. Mark ⁇ denotes that the number of samples rates o was within the range of 3 - 7 out of 10 samples. Test results are shown in Table 1.
• Polyvinyl chloride can hardly be used for the purpose of thin coating for space saving to which the invention directed, and in environmental conditions in which vibration at hot temperatures is involved.
• Coating was made with copolymer P at 0.3 mm and 0.4 mm coat thickness settings in same was as in Example 1, except that no adjustment was made of discharge pressure by gear pump at the stage of the covering operation.
• the mean concen­tricity values of the covering materials obtained were 66% and 70% respectively.

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• Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Organic Insulating Materials (AREA)
• Insulated Conductors (AREA)
• Polyesters Or Polycarbonates (AREA)

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• 1987
  • 1987-02-23 JP JP62039613A patent/JPS63207003A/ja active Pending
• 1988
  • 1988-02-03 KR KR1019880000979A patent/KR910001033B1/ko not_active IP Right Cessation
  • 1988-02-22 DE DE8888301470T patent/DE3873128T2/de not_active Expired - Lifetime
  • 1988-02-22 EP EP88301470A patent/EP0284201B1/de not_active Expired - Lifetime
  • 1988-02-23 AU AU12050/88A patent/AU603428B2/en not_active Ceased
  • 1988-02-23 US US07/159,121 patent/US4913964A/en not_active Expired - Fee Related

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